Run results for: defineproperty (data property) vs direct assignment

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/132.0.0.0 Safari/537.36

Browser: Chrome 132

Operating system: Windows

Device Platform: Desktop

Date tested: one year ago

77K/s

3K/s

View exact numbers

Test name	Executions per second
✓ b	77,188 Ops/sec
a	2,770 Ops/sec

Tests:

a
var target = {}; var key = 'something'; for (var i=0; i<1000; i++) { Object.defineProperty(target, key+i, { configurable: true, enumerable: true, writable: false, value: undefined, }); }
b
var target = {}; var key = 'something'; for (var i=0; i<1000; i++) { target[key+1] = undefined; }